PTFE sealing lips are PTFE compound discs that are mechanically formed to a diameter slightly smaller than the shaft. The forming of the lip creats a shape that takes advantage of the hoop strength of the PTFE compound discs. This hoop strength provides the load that is critical for low or no pressure applications to obtain a positive seal.
The sealing element typically has a smooth surface contacting the shaft. For applications sealing liquid at below 0.1Mpa, a hydrodynamic spiral feature can be machined into the surface of the sealing element to provide a positive pumping action to drive fluid away from the air side of the seal.It is critical to match the seal to the shaft rotation to ensure positive sealing. The hydrodynamic spiral feature have three kind,Single start,Double start and Triple start.Direction of rotation:CCW or CW.
As we konw, PTFE surface can adhere with other material after etching PTFE surface. We have Automatic etched PTFE surface machine,can etch 100000pcs PTFE lips each day.